Merge "Fix kernel header scrubbing for LP64."
diff --git a/libc/Android.mk b/libc/Android.mk
index 76425c1..e4e58b7 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -95,6 +95,8 @@
     bionic/__memmove_chk.cpp \
     bionic/__read_chk.cpp \
     bionic/__recvfrom_chk.cpp \
+    bionic/__stpcpy_chk.cpp \
+    bionic/__stpncpy_chk.cpp \
     bionic/__strchr_chk.cpp \
     bionic/__strlcat_chk.cpp \
     bionic/__strlcpy_chk.cpp \
@@ -382,6 +384,8 @@
     upstream-openbsd/lib/libc/stdlib/strtoull.c \
     upstream-openbsd/lib/libc/stdlib/strtoumax.c \
     upstream-openbsd/lib/libc/stdlib/system.c \
+    upstream-openbsd/lib/libc/string/stpcpy.c \
+    upstream-openbsd/lib/libc/string/stpncpy.c \
     upstream-openbsd/lib/libc/string/strcasecmp.c \
     upstream-openbsd/lib/libc/string/strcspn.c \
     upstream-openbsd/lib/libc/string/strdup.c \
diff --git a/libc/bionic/__stpcpy_chk.cpp b/libc/bionic/__stpcpy_chk.cpp
new file mode 100644
index 0000000..3ce81ee
--- /dev/null
+++ b/libc/bionic/__stpcpy_chk.cpp
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#undef _FORTIFY_SOURCE
+
+#include <string.h>
+#include <stdlib.h>
+#include "private/libc_logging.h"
+
+/*
+ * Runtime implementation of __builtin____stpcpy_chk.
+ *
+ * See
+ *   http://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
+ *   http://gcc.gnu.org/ml/gcc-patches/2004-09/msg02055.html
+ * for details.
+ *
+ * This stpcpy check is called if _FORTIFY_SOURCE is defined and
+ * greater than 0.
+ */
+extern "C" char* __stpcpy_chk(char* dest, const char* src, size_t dest_len) {
+  // TODO: optimize so we don't scan src twice.
+  size_t src_len = strlen(src) + 1;
+  if (__predict_false(src_len > dest_len)) {
+    __fortify_chk_fail("stpcpy: prevented write past end of buffer",
+                       BIONIC_EVENT_STPCPY_BUFFER_OVERFLOW);
+  }
+
+  return stpcpy(dest, src);
+}
diff --git a/libc/bionic/__stpncpy_chk.cpp b/libc/bionic/__stpncpy_chk.cpp
new file mode 100644
index 0000000..6c9215c
--- /dev/null
+++ b/libc/bionic/__stpncpy_chk.cpp
@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#undef _FORTIFY_SOURCE
+
+#include <string.h>
+#include <stdlib.h>
+#include "private/libc_logging.h"
+
+/*
+ * Runtime implementation of __builtin____stpncpy_chk.
+ *
+ * See
+ *   http://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
+ *   http://gcc.gnu.org/ml/gcc-patches/2004-09/msg02055.html
+ * for details.
+ *
+ * This stpncpy check is called if _FORTIFY_SOURCE is defined and
+ * greater than 0.
+ */
+extern "C" char* __stpncpy_chk(char* __restrict dest, const char* __restrict src,
+                               size_t len, size_t dest_len) {
+  if (__predict_false(len > dest_len)) {
+    __fortify_chk_fail("stpncpy: prevented write past end of buffer",
+                       BIONIC_EVENT_STPNCPY_BUFFER_OVERFLOW);
+  }
+
+  return stpncpy(dest, src, len);
+}
+
+/*
+ * __stpncpy_chk2
+ *
+ * This is a variant of __stpncpy_chk, but it also checks to make
+ * sure we don't read beyond the end of "src". The code for this is
+ * based on the original version of stpncpy, but modified to check
+ * how much we read from "src" at the end of the copy operation.
+ */
+extern "C" char* __stpncpy_chk2(char* __restrict dst, const char* __restrict src,
+              size_t n, size_t dest_len, size_t src_len)
+{
+  if (__predict_false(n > dest_len)) {
+    __fortify_chk_fail("stpncpy: prevented write past end of buffer",
+                       BIONIC_EVENT_STPNCPY_BUFFER_OVERFLOW);
+  }
+  if (n != 0) {
+    char* d = dst;
+    const char* s = src;
+
+    do {
+      if ((*d++ = *s++) == 0) {
+        /* NUL pad the remaining n-1 bytes */
+        while (--n != 0) {
+          *d++ = 0;
+        }
+        break;
+      }
+    } while (--n != 0);
+
+    size_t s_copy_len = static_cast<size_t>(s - src);
+    if (__predict_false(s_copy_len > src_len)) {
+      __fortify_chk_fail("stpncpy: prevented read past end of buffer", 0);
+    }
+  }
+
+  return dst;
+}
diff --git a/libc/bionic/__strcpy_chk.cpp b/libc/bionic/__strcpy_chk.cpp
index 1f6bc80..ad3ef50 100644
--- a/libc/bionic/__strcpy_chk.cpp
+++ b/libc/bionic/__strcpy_chk.cpp
@@ -26,6 +26,8 @@
  * SUCH DAMAGE.
  */
 
+#undef _FORTIFY_SOURCE
+
 #include <string.h>
 #include <stdlib.h>
 #include "private/libc_logging.h"
@@ -41,7 +43,7 @@
  * This strcpy check is called if _FORTIFY_SOURCE is defined and
  * greater than 0.
  */
-extern "C" char* __strcpy_chk (char* dest, const char* src, size_t dest_len) {
+extern "C" char* __strcpy_chk(char* dest, const char* src, size_t dest_len) {
   // TODO: optimize so we don't scan src twice.
   size_t src_len = strlen(src) + 1;
   if (__predict_false(src_len > dest_len)) {
diff --git a/libc/include/string.h b/libc/include/string.h
index ec998ed..c9ae03b 100644
--- a/libc/include/string.h
+++ b/libc/include/string.h
@@ -53,6 +53,7 @@
 extern size_t strlen(const char *) __purefunc;
 extern size_t __strlen_chk(const char *, size_t);
 extern int    strcmp(const char *, const char *) __purefunc;
+extern char*  stpcpy(char* __restrict, const char* __restrict);
 extern char*  strcpy(char* __restrict, const char* __restrict);
 extern char*  strcat(char* __restrict, const char* __restrict);
 
@@ -72,6 +73,7 @@
 extern char*  strncat(char* __restrict, const char* __restrict, size_t);
 extern char*  strndup(const char *, size_t);
 extern int    strncmp(const char *, const char *, size_t) __purefunc;
+extern char*  stpncpy(char* __restrict, const char* __restrict, size_t);
 extern char*  strncpy(char* __restrict, const char* __restrict, size_t);
 
 extern size_t strlcat(char* __restrict, const char* __restrict, size_t);
@@ -89,8 +91,8 @@
 
 #if defined(__BIONIC_FORTIFY)
 
-__errordecl(__memcpy_dest_size_error, "memcpy called with size bigger than destination");
-__errordecl(__memcpy_src_size_error, "memcpy called with size bigger than source");
+__errordecl(__memcpy_dest_size_error, "memcpy: prevented write past end of buffer");
+__errordecl(__memcpy_src_size_error, "memcpy: prevented read past end of buffer");
 
 __BIONIC_FORTIFY_INLINE
 void* memcpy(void* __restrict dest, const void* __restrict src, size_t copy_amount) {
@@ -116,11 +118,43 @@
 }
 
 __BIONIC_FORTIFY_INLINE
+char* stpcpy(char* __restrict dest, const char* __restrict src) {
+    return __builtin___stpcpy_chk(dest, src, __bos(dest));
+}
+
+__BIONIC_FORTIFY_INLINE
 char* strcpy(char* __restrict dest, const char* __restrict src) {
     return __builtin___strcpy_chk(dest, src, __bos(dest));
 }
 
-__errordecl(__strncpy_error, "strncpy called with size bigger than buffer");
+__errordecl(__stpncpy_error, "stpncpy: prevented write past end of buffer");
+extern char* __stpncpy_chk2(char* __restrict, const char* __restrict, size_t, size_t, size_t);
+
+__BIONIC_FORTIFY_INLINE
+char* stpncpy(char* __restrict dest, const char* __restrict src, size_t n) {
+    size_t bos_dest = __bos(dest);
+    size_t bos_src = __bos(src);
+    if (__builtin_constant_p(n) && (n > bos_dest)) {
+        __stpncpy_error();
+    }
+
+    if (bos_src == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
+        return __builtin___stpncpy_chk(dest, src, n, bos_dest);
+    }
+
+    if (__builtin_constant_p(n) && (n <= bos_src)) {
+        return __builtin___stpncpy_chk(dest, src, n, bos_dest);
+    }
+
+    size_t slen = __builtin_strlen(src);
+    if (__builtin_constant_p(slen)) {
+        return __builtin___stpncpy_chk(dest, src, n, bos_dest);
+    }
+
+    return __stpncpy_chk2(dest, src, n, bos_dest, bos_src);
+}
+
+__errordecl(__strncpy_error, "strncpy: prevented write past end of buffer");
 extern char* __strncpy_chk2(char* __restrict, const char* __restrict, size_t, size_t, size_t);
 
 __BIONIC_FORTIFY_INLINE
@@ -164,7 +198,7 @@
 
 extern size_t __strlcpy_real(char* __restrict, const char* __restrict, size_t)
     __asm__(__USER_LABEL_PREFIX__ "strlcpy");
-__errordecl(__strlcpy_error, "strlcpy called with size bigger than buffer");
+__errordecl(__strlcpy_error, "strlcpy: prevented write past end of buffer");
 extern size_t __strlcpy_chk(char *, const char *, size_t, size_t);
 
 __BIONIC_FORTIFY_INLINE
@@ -195,7 +229,7 @@
 
 extern size_t __strlcat_real(char* __restrict, const char* __restrict, size_t)
     __asm__(__USER_LABEL_PREFIX__ "strlcat");
-__errordecl(__strlcat_error, "strlcat called with size bigger than buffer");
+__errordecl(__strlcat_error, "strlcat: prevented write past end of buffer");
 extern size_t __strlcat_chk(char* __restrict, const char* __restrict, size_t, size_t);
 
 
diff --git a/libc/private/libc_events.h b/libc/private/libc_events.h
index 5d20f4b..f2b973d 100644
--- a/libc/private/libc_events.h
+++ b/libc/private/libc_events.h
@@ -40,6 +40,8 @@
 #define BIONIC_EVENT_STRNCPY_BUFFER_OVERFLOW  80120
 #define BIONIC_EVENT_MEMSET_BUFFER_OVERFLOW   80125
 #define BIONIC_EVENT_STRCPY_BUFFER_OVERFLOW   80130
+#define BIONIC_EVENT_STPCPY_BUFFER_OVERFLOW   80135
+#define BIONIC_EVENT_STPNCPY_BUFFER_OVERFLOW  80140
 
 #define BIONIC_EVENT_RESOLVER_OLD_RESPONSE    80300
 #define BIONIC_EVENT_RESOLVER_WRONG_SERVER    80305
diff --git a/libc/upstream-openbsd/lib/libc/string/stpcpy.c b/libc/upstream-openbsd/lib/libc/string/stpcpy.c
new file mode 100644
index 0000000..d3d61e0
--- /dev/null
+++ b/libc/upstream-openbsd/lib/libc/string/stpcpy.c
@@ -0,0 +1,44 @@
+/*	$OpenBSD: stpcpy.c,v 1.1 2012/01/17 02:48:01 guenther Exp $	*/
+
+/*
+ * Copyright (c) 1988 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <string.h>
+
+#if defined(APIWARN)
+__warn_references(stpcpy,
+    "warning: stpcpy() is dangerous GNU crap; don't use it");
+#endif
+
+char *
+stpcpy(char *to, const char *from)
+{
+	for (; (*to = *from) != '\0'; ++from, ++to);
+	return(to);
+}
diff --git a/libc/upstream-openbsd/lib/libc/string/stpncpy.c b/libc/upstream-openbsd/lib/libc/string/stpncpy.c
new file mode 100644
index 0000000..c7c2a57
--- /dev/null
+++ b/libc/upstream-openbsd/lib/libc/string/stpncpy.c
@@ -0,0 +1,56 @@
+/*	$OpenBSD: stpncpy.c,v 1.2 2012/07/11 10:44:59 naddy Exp $	*/
+
+/*-
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Chris Torek.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <string.h>
+
+char *
+stpncpy(char *dst, const char *src, size_t n)
+{
+	if (n != 0) {
+		char *d = dst;
+		const char *s = src;
+
+		dst = &dst[n];
+		do {
+			if ((*d++ = *s++) == 0) {
+				dst = d - 1;
+				/* NUL pad the remaining n-1 bytes */
+				while (--n != 0)
+					*d++ = 0;
+				break;
+			}
+		} while (--n != 0);
+	}
+	return (dst);
+}
diff --git a/tests/fortify_test.cpp b/tests/fortify_test.cpp
index 67e197e..d80b2f7 100644
--- a/tests/fortify_test.cpp
+++ b/tests/fortify_test.cpp
@@ -43,6 +43,31 @@
 #ifndef __clang__
 // This test is disabled in clang because clang doesn't properly detect
 // this buffer overflow. TODO: Fix clang.
+TEST(DEATHTEST, stpncpy_fortified2) {
+  ::testing::FLAGS_gtest_death_test_style = "threadsafe";
+  foo myfoo;
+  int copy_amt = atoi("11");
+  ASSERT_EXIT(stpncpy(myfoo.a, "01234567890", copy_amt),
+              testing::KilledBySignal(SIGABRT), "");
+}
+#endif
+
+#ifndef __clang__
+// This test is disabled in clang because clang doesn't properly detect
+// this buffer overflow. TODO: Fix clang.
+TEST(DEATHTEST, stpncpy2_fortified2) {
+  ::testing::FLAGS_gtest_death_test_style = "threadsafe";
+  foo myfoo;
+  memset(&myfoo, 0, sizeof(myfoo));
+  myfoo.one[0] = 'A'; // not null terminated string
+  ASSERT_EXIT(stpncpy(myfoo.b, myfoo.one, sizeof(myfoo.b)),
+              testing::KilledBySignal(SIGABRT), "");
+}
+#endif
+
+#ifndef __clang__
+// This test is disabled in clang because clang doesn't properly detect
+// this buffer overflow. TODO: Fix clang.
 TEST(DEATHTEST, strncpy_fortified2) {
   ::testing::FLAGS_gtest_death_test_style = "threadsafe";
   foo myfoo;
@@ -144,6 +169,24 @@
 // zero sized target with "\0" source (should fail)
 // This test is disabled in clang because clang doesn't properly detect
 // this buffer overflow. TODO: Fix clang.
+TEST(DEATHTEST, stpcpy_fortified2) {
+#if defined(__BIONIC__)
+  ::testing::FLAGS_gtest_death_test_style = "threadsafe";
+  foo myfoo;
+  char* src = strdup("");
+  ASSERT_EXIT(stpcpy(myfoo.empty, src),
+              testing::KilledBySignal(SIGABRT), "");
+  free(src);
+#else // __BIONIC__
+  GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif // __BIONIC__
+}
+#endif
+
+#ifndef __clang__
+// zero sized target with "\0" source (should fail)
+// This test is disabled in clang because clang doesn't properly detect
+// this buffer overflow. TODO: Fix clang.
 TEST(DEATHTEST, strcpy_fortified2) {
 #if defined(__BIONIC__)
   ::testing::FLAGS_gtest_death_test_style = "threadsafe";
@@ -559,6 +602,23 @@
   ASSERT_EXIT(memcpy(bufb, bufa, n), testing::KilledBySignal(SIGABRT), "");
 }
 
+TEST(DEATHTEST, stpncpy_fortified) {
+  ::testing::FLAGS_gtest_death_test_style = "threadsafe";
+  char bufa[15];
+  char bufb[10];
+  strcpy(bufa, "01234567890123");
+  size_t n = strlen(bufa);
+  ASSERT_EXIT(stpncpy(bufb, bufa, n), testing::KilledBySignal(SIGABRT), "");
+}
+
+TEST(DEATHTEST, stpncpy2_fortified) {
+  ::testing::FLAGS_gtest_death_test_style = "threadsafe";
+  char dest[11];
+  char src[10];
+  memcpy(src, "0123456789", sizeof(src)); // src is not null terminated
+  ASSERT_EXIT(stpncpy(dest, src, sizeof(dest)), testing::KilledBySignal(SIGABRT), "");
+}
+
 TEST(DEATHTEST, strncpy_fortified) {
   ::testing::FLAGS_gtest_death_test_style = "threadsafe";
   char bufa[15];
@@ -568,6 +628,7 @@
   ASSERT_EXIT(strncpy(bufb, bufa, n), testing::KilledBySignal(SIGABRT), "");
 }
 
+
 TEST(DEATHTEST, strncpy2_fortified) {
   ::testing::FLAGS_gtest_death_test_style = "threadsafe";
   char dest[11];
@@ -790,6 +851,45 @@
   ASSERT_EQ('\0',  buf[9]);
 }
 
+TEST(TEST_NAME, stpncpy) {
+  char src[10];
+  char dst[10];
+  memcpy(src, "0123456789", sizeof(src)); // non null terminated string
+  stpncpy(dst, src, sizeof(dst));
+  ASSERT_EQ('0', dst[0]);
+  ASSERT_EQ('1', dst[1]);
+  ASSERT_EQ('2', dst[2]);
+  ASSERT_EQ('3', dst[3]);
+  ASSERT_EQ('4', dst[4]);
+  ASSERT_EQ('5', dst[5]);
+  ASSERT_EQ('6', dst[6]);
+  ASSERT_EQ('7', dst[7]);
+  ASSERT_EQ('8', dst[8]);
+  ASSERT_EQ('9', dst[9]);
+}
+
+TEST(TEST_NAME, stpncpy2) {
+  char src[10];
+  char dst[15];
+  memcpy(src, "012345678\0", sizeof(src));
+  stpncpy(dst, src, sizeof(dst));
+  ASSERT_EQ('0',  dst[0]);
+  ASSERT_EQ('1',  dst[1]);
+  ASSERT_EQ('2',  dst[2]);
+  ASSERT_EQ('3',  dst[3]);
+  ASSERT_EQ('4',  dst[4]);
+  ASSERT_EQ('5',  dst[5]);
+  ASSERT_EQ('6',  dst[6]);
+  ASSERT_EQ('7',  dst[7]);
+  ASSERT_EQ('8',  dst[8]);
+  ASSERT_EQ('\0', dst[9]);
+  ASSERT_EQ('\0', dst[10]);
+  ASSERT_EQ('\0', dst[11]);
+  ASSERT_EQ('\0', dst[12]);
+  ASSERT_EQ('\0', dst[13]);
+  ASSERT_EQ('\0', dst[14]);
+}
+
 TEST(TEST_NAME, strncpy) {
   char src[10];
   char dst[10];
@@ -848,22 +948,22 @@
   ASSERT_EQ('\0', buf[9]);
 }
 
+extern "C" char* __stpcpy_chk(char*, const char*, size_t);
+
+TEST(TEST_NAME, stpcpy_chk_max_int_size) {
+  char buf[10];
+  char* res = __stpcpy_chk(buf, "012345678", (size_t)-1);
+  ASSERT_EQ(buf + strlen("012345678"), res);
+  ASSERT_STREQ("012345678", buf);
+}
+
 extern "C" char* __strcpy_chk(char*, const char*, size_t);
 
 TEST(TEST_NAME, strcpy_chk_max_int_size) {
   char buf[10];
   char* res = __strcpy_chk(buf, "012345678", (size_t)-1);
   ASSERT_EQ(buf, res);
-  ASSERT_EQ('0',  buf[0]);
-  ASSERT_EQ('1',  buf[1]);
-  ASSERT_EQ('2',  buf[2]);
-  ASSERT_EQ('3',  buf[3]);
-  ASSERT_EQ('4',  buf[4]);
-  ASSERT_EQ('5',  buf[5]);
-  ASSERT_EQ('6',  buf[6]);
-  ASSERT_EQ('7',  buf[7]);
-  ASSERT_EQ('8',  buf[8]);
-  ASSERT_EQ('\0', buf[9]);
+  ASSERT_STREQ("012345678", buf);
 }
 
 extern "C" void* __memcpy_chk(void*, const void*, size_t, size_t);
diff --git a/tests/string_test.cpp b/tests/string_test.cpp
index c35976a..14b284e 100644
--- a/tests/string_test.cpp
+++ b/tests/string_test.cpp
@@ -222,7 +222,7 @@
 TEST(string, strcpy2) {
   char buf[1];
   char* orig = strdup("");
-  strcpy(buf, orig);
+  ASSERT_EQ(buf, strcpy(buf, orig));
   ASSERT_EQ('\0', buf[0]);
   free(orig);
 }
@@ -232,13 +232,8 @@
   char buf[10];
   char* orig = strdup("12345");
   memset(buf, 'A', sizeof(buf));
-  strcpy(buf, orig);
-  ASSERT_EQ('1',  buf[0]);
-  ASSERT_EQ('2',  buf[1]);
-  ASSERT_EQ('3',  buf[2]);
-  ASSERT_EQ('4',  buf[3]);
-  ASSERT_EQ('5',  buf[4]);
-  ASSERT_EQ('\0', buf[5]);
+  ASSERT_EQ(buf, strcpy(buf, orig));
+  ASSERT_STREQ("12345", buf);
   ASSERT_EQ('A',  buf[6]);
   ASSERT_EQ('A',  buf[7]);
   ASSERT_EQ('A',  buf[8]);
@@ -251,17 +246,41 @@
   char buf[10];
   char* orig = strdup("123456789");
   memset(buf, 'A', sizeof(buf));
-  strcpy(buf, orig);
-  ASSERT_EQ('1',  buf[0]);
-  ASSERT_EQ('2',  buf[1]);
-  ASSERT_EQ('3',  buf[2]);
-  ASSERT_EQ('4',  buf[3]);
-  ASSERT_EQ('5',  buf[4]);
-  ASSERT_EQ('6',  buf[5]);
-  ASSERT_EQ('7',  buf[6]);
-  ASSERT_EQ('8',  buf[7]);
-  ASSERT_EQ('9',  buf[8]);
-  ASSERT_EQ('\0', buf[9]);
+  ASSERT_EQ(buf, strcpy(buf, orig));
+  ASSERT_STREQ("123456789", buf);
+  free(orig);
+}
+
+// one byte target with "\0" source
+TEST(string, stpcpy2) {
+  char buf[1];
+  char* orig = strdup("");
+  ASSERT_EQ(buf, stpcpy(buf, orig));
+  ASSERT_EQ('\0', buf[0]);
+  free(orig);
+}
+
+// multibyte target where we under fill target
+TEST(string, stpcpy3) {
+  char buf[10];
+  char* orig = strdup("12345");
+  memset(buf, 'A', sizeof(buf));
+  ASSERT_EQ(buf+strlen(orig), stpcpy(buf, orig));
+  ASSERT_STREQ("12345", buf);
+  ASSERT_EQ('A',  buf[6]);
+  ASSERT_EQ('A',  buf[7]);
+  ASSERT_EQ('A',  buf[8]);
+  ASSERT_EQ('A',  buf[9]);
+  free(orig);
+}
+
+// multibyte target where we fill target exactly
+TEST(string, stpcpy4) {
+  char buf[10];
+  char* orig = strdup("123456789");
+  memset(buf, 'A', sizeof(buf));
+  ASSERT_EQ(buf+strlen(orig), stpcpy(buf, orig));
+  ASSERT_STREQ("123456789", buf);
   free(orig);
 }
 
@@ -272,13 +291,7 @@
   buf[1] = '\0';
   char* res = strcat(buf, "01234");
   ASSERT_EQ(buf, res);
-  ASSERT_EQ('a',  buf[0]);
-  ASSERT_EQ('0',  buf[1]);
-  ASSERT_EQ('1',  buf[2]);
-  ASSERT_EQ('2',  buf[3]);
-  ASSERT_EQ('3',  buf[4]);
-  ASSERT_EQ('4',  buf[5]);
-  ASSERT_EQ('\0', buf[6]);
+  ASSERT_STREQ("a01234", buf);
   ASSERT_EQ('A',  buf[7]);
   ASSERT_EQ('A',  buf[8]);
   ASSERT_EQ('A',  buf[9]);
@@ -291,16 +304,7 @@
   buf[1] = '\0';
   char* res = strcat(buf, "01234567");
   ASSERT_EQ(buf, res);
-  ASSERT_EQ('a',  buf[0]);
-  ASSERT_EQ('0',  buf[1]);
-  ASSERT_EQ('1',  buf[2]);
-  ASSERT_EQ('2',  buf[3]);
-  ASSERT_EQ('3',  buf[4]);
-  ASSERT_EQ('4',  buf[5]);
-  ASSERT_EQ('5', buf[6]);
-  ASSERT_EQ('6',  buf[7]);
-  ASSERT_EQ('7',  buf[8]);
-  ASSERT_EQ('\0',  buf[9]);
+  ASSERT_STREQ("a01234567", buf);
 }
 
 TEST(string, strncat2) {
@@ -310,13 +314,7 @@
   buf[1] = '\0';
   char* res = strncat(buf, "01234", sizeof(buf) - strlen(buf) - 1);
   ASSERT_EQ(buf, res);
-  ASSERT_EQ('a',  buf[0]);
-  ASSERT_EQ('0',  buf[1]);
-  ASSERT_EQ('1',  buf[2]);
-  ASSERT_EQ('2',  buf[3]);
-  ASSERT_EQ('3',  buf[4]);
-  ASSERT_EQ('4',  buf[5]);
-  ASSERT_EQ('\0', buf[6]);
+  ASSERT_STREQ("a01234", buf);
   ASSERT_EQ('A',  buf[7]);
   ASSERT_EQ('A',  buf[8]);
   ASSERT_EQ('A',  buf[9]);
@@ -329,13 +327,7 @@
   buf[1] = '\0';
   char* res = strncat(buf, "0123456789", 5);
   ASSERT_EQ(buf, res);
-  ASSERT_EQ('a',  buf[0]);
-  ASSERT_EQ('0',  buf[1]);
-  ASSERT_EQ('1',  buf[2]);
-  ASSERT_EQ('2',  buf[3]);
-  ASSERT_EQ('3',  buf[4]);
-  ASSERT_EQ('4',  buf[5]);
-  ASSERT_EQ('\0', buf[6]);
+  ASSERT_STREQ("a01234", buf);
   ASSERT_EQ('A',  buf[7]);
   ASSERT_EQ('A',  buf[8]);
   ASSERT_EQ('A',  buf[9]);
@@ -348,16 +340,7 @@
   buf[1] = '\0';
   char* res = strncat(buf, "01234567", 8);
   ASSERT_EQ(buf, res);
-  ASSERT_EQ('a',  buf[0]);
-  ASSERT_EQ('0',  buf[1]);
-  ASSERT_EQ('1',  buf[2]);
-  ASSERT_EQ('2',  buf[3]);
-  ASSERT_EQ('3',  buf[4]);
-  ASSERT_EQ('4',  buf[5]);
-  ASSERT_EQ('5', buf[6]);
-  ASSERT_EQ('6',  buf[7]);
-  ASSERT_EQ('7',  buf[8]);
-  ASSERT_EQ('\0',  buf[9]);
+  ASSERT_STREQ("a01234567", buf);
 }
 
 TEST(string, strncat5) {
@@ -367,16 +350,7 @@
   buf[1] = '\0';
   char* res = strncat(buf, "01234567", 9);
   ASSERT_EQ(buf, res);
-  ASSERT_EQ('a',  buf[0]);
-  ASSERT_EQ('0',  buf[1]);
-  ASSERT_EQ('1',  buf[2]);
-  ASSERT_EQ('2',  buf[3]);
-  ASSERT_EQ('3',  buf[4]);
-  ASSERT_EQ('4',  buf[5]);
-  ASSERT_EQ('5', buf[6]);
-  ASSERT_EQ('6',  buf[7]);
-  ASSERT_EQ('7',  buf[8]);
-  ASSERT_EQ('\0',  buf[9]);
+  ASSERT_STREQ("a01234567", buf);
 }
 
 TEST(string, strchr_with_0) {
@@ -456,6 +430,32 @@
   }
 }
 
+TEST(string, stpcpy) {
+  StringTestState<char> state(SMALL);
+  for (size_t j = 0; j < POS_ITER; j++) {
+    state.NewIteration();
+
+    size_t pos = random() % state.MAX_LEN;
+
+    memset(state.ptr1, '\2', pos);
+    state.ptr1[pos] = '\0';
+    state.ptr1[state.MAX_LEN - 1] = '\0';
+
+    memcpy(state.ptr, state.ptr1, state.MAX_LEN);
+
+    memset(state.ptr2, '\1', state.MAX_LEN);
+    state.ptr2[state.MAX_LEN - 1] = '\0';
+
+    memset(state.ptr + state.MAX_LEN, '\1', state.MAX_LEN);
+    memcpy(state.ptr + state.MAX_LEN, state.ptr1, pos + 1);
+    state.ptr[2 * state.MAX_LEN - 1] = '\0';
+
+    ASSERT_TRUE(stpcpy(state.ptr2, state.ptr1) == state.ptr2 + strlen(state.ptr1));
+    ASSERT_FALSE((memcmp(state.ptr1, state.ptr, state.MAX_LEN)) != 0 ||
+                 (memcmp(state.ptr2, state.ptr + state.MAX_LEN, state.MAX_LEN) != 0));
+  }
+}
+
 TEST(string, strcpy) {
   StringTestState<char> state(SMALL);
   for (size_t j = 0; j < POS_ITER; j++) {
@@ -482,7 +482,6 @@
   }
 }
 
-
 TEST(string, strlcat) {
 #if defined(__BIONIC__)
   StringTestState<char> state(SMALL);
@@ -614,30 +613,81 @@
   }
 }
 
+TEST(string, stpncpy) {
+  StringTestState<char> state(SMALL);
+  for (size_t j = 0; j < ITER; j++) {
+    state.NewIteration();
+
+    // Choose a random value to fill the string, except \0 (string terminator),
+    // or \1 (guarantees it's different from anything in ptr2).
+    memset(state.ptr1, (random() % 254) + 2, state.MAX_LEN);
+    // Choose a random size for our src buffer.
+    size_t ptr1_len = random() % state.MAX_LEN;
+    state.ptr1[ptr1_len] = '\0';
+    // Copy ptr1 into ptr, used to verify that ptr1 does not get modified.
+    memcpy(state.ptr, state.ptr1, state.MAX_LEN);
+    // Init ptr2 to a set value.
+    memset(state.ptr2, '\1', state.MAX_LEN);
+
+    // Choose a random amount of data to copy.
+    size_t copy_len = random() % state.MAX_LEN;
+
+    // Set the second half of ptr to the expected pattern in ptr2.
+    memset(state.ptr + state.MAX_LEN, '\1', state.MAX_LEN);
+    memcpy(state.ptr + state.MAX_LEN, state.ptr1, copy_len);
+    size_t expected_end;
+    if (copy_len > ptr1_len) {
+      memset(state.ptr + state.MAX_LEN + ptr1_len, '\0', copy_len - ptr1_len);
+      expected_end = ptr1_len;
+    } else {
+      expected_end = copy_len;
+    }
+
+    ASSERT_EQ(state.ptr2 + expected_end, stpncpy(state.ptr2, state.ptr1, copy_len));
+
+    // Verify ptr1 was not modified.
+    ASSERT_EQ(0, memcmp(state.ptr1, state.ptr, state.MAX_LEN));
+    // Verify ptr2 contains the expected data.
+    ASSERT_EQ(0, memcmp(state.ptr2, state.ptr + state.MAX_LEN, state.MAX_LEN));
+  }
+}
+
 TEST(string, strncpy) {
   StringTestState<char> state(SMALL);
   for (size_t j = 0; j < ITER; j++) {
     state.NewIteration();
 
-    memset(state.ptr1, random() & 255, state.MAX_LEN);
-    state.ptr1[random () % state.MAX_LEN] = '\0';
+    // Choose a random value to fill the string, except \0 (string terminator),
+    // or \1 (guarantees it's different from anything in ptr2).
+    memset(state.ptr1, (random() % 254) + 2, state.MAX_LEN);
+    // Choose a random size for our src buffer.
+    size_t ptr1_len = random() % state.MAX_LEN;
+    state.ptr1[ptr1_len] = '\0';
+    // Copy ptr1 into ptr, used to verify that ptr1 does not get modified.
     memcpy(state.ptr, state.ptr1, state.MAX_LEN);
-
+    // Init ptr2 to a set value.
     memset(state.ptr2, '\1', state.MAX_LEN);
 
-    size_t pos;
-    if (memchr(state.ptr1, 0, state.MAX_LEN)) {
-      pos = strlen(state.ptr1);
+    // Choose a random amount of data to copy.
+    size_t copy_len = random() % state.MAX_LEN;
+
+    // Set the second half of ptr to the expected pattern in ptr2.
+    memset(state.ptr + state.MAX_LEN, '\1', state.MAX_LEN);
+    memcpy(state.ptr + state.MAX_LEN, state.ptr1, copy_len);
+    size_t expected_end;
+    if (copy_len > ptr1_len) {
+      memset(state.ptr + state.MAX_LEN + ptr1_len, '\0', copy_len - ptr1_len);
+      expected_end = ptr1_len;
     } else {
-      pos = state.MAX_LEN - 1;
+      expected_end = copy_len;
     }
 
-    memset(state.ptr + state.MAX_LEN, '\0', state.MAX_LEN);
-    memcpy(state.ptr + state.MAX_LEN, state.ptr1, pos + 1);
+    ASSERT_EQ(state.ptr2 + expected_end, stpncpy(state.ptr2, state.ptr1, copy_len));
 
-    ASSERT_TRUE(strncpy(state.ptr2, state.ptr1, state.MAX_LEN) == state.ptr2);
-    ASSERT_FALSE(memcmp(state.ptr1, state.ptr, state.MAX_LEN) != 0 ||
-                 memcmp(state.ptr2, state.ptr + state.MAX_LEN, state.MAX_LEN) != 0);
+    // Verify ptr1 was not modified.
+    ASSERT_EQ(0, memcmp(state.ptr1, state.ptr, state.MAX_LEN));
+    // Verify ptr2 contains the expected data.
+    ASSERT_EQ(0, memcmp(state.ptr2, state.ptr + state.MAX_LEN, state.MAX_LEN));
   }
 }
 
@@ -966,6 +1016,25 @@
   RunSrcDstBufferOverreadTest(DoStrcpyTest);
 }
 
+static void DoStpcpyTest(uint8_t* src, uint8_t* dst, size_t len) {
+  if (len >= 1) {
+    memset(src, (32 + (len % 96)), len - 1);
+    src[len-1] = '\0';
+    memset(dst, 0, len);
+    ASSERT_EQ(dst+len-1, reinterpret_cast<uint8_t*>(stpcpy(reinterpret_cast<char*>(dst),
+                                                           reinterpret_cast<char*>(src))));
+    ASSERT_TRUE(memcmp(src, dst, len) == 0);
+  }
+}
+
+TEST(string, stpcpy_align) {
+  RunSrcDstBufferAlignTest(LARGE, DoStpcpyTest);
+}
+
+TEST(string, stpcpy_overread) {
+  RunSrcDstBufferOverreadTest(DoStpcpyTest);
+}
+
 // Use our own incrementer to cut down on the total number of calls.
 static size_t LargeSetIncrement(size_t len) {
   if (len >= 4096) {